Pain Affects Quality of Life for Billions of People Worldwide

Treating pain is at the heart of medicine and is an essential role of every clinician.  Unmanaged pain delays recovery, increases morbidity and mortality, and overburdens healthcare resources, with annual healthcare costs exceeding $600 billion in the U.S. alone.

Despite the prevalence of pain, there are currently no clinically accepted tools to objectively assess pain. Clinicians rely on a patients’ subjective assessments, or to simply guess when patients cannot describe their pain (e.g. anesthetized, babies, dementia etc.).

Currently, the diagnosis of pain levels and recommendations on pain-management strategies are mostly based on patients’ subjective report of their pain level and incidence. An objective assessment enables clinicians to provide personalized and effective pain care.


Nociception - Pain in anesthetized patients


Objective assessment of nociception in anesthetized patients is a key challenge in medicine.

During general anesthesia, a patients’ body reacts to painful stimuli – although it is not consciously recognized. This intraoperative pain can stress the patient’s
body 1, 2, 3, 4 and worsen pain after surgery. As the patient cannot communicate it is hard for clinicians to evaluate.

Throughout the surgical procedure, anesthetized patients are continuously monitored for hypnosis and muscle relaxation. Nociception/analgesia are currently assessed by monitoring changes in heart rate (HR), blood pressure (BP), and other indirect parameters which are not sensitive or specific to nociception.

Consequently, the patient may be given insufficient analgesia, which can promote postoperative pain, or excessive analgesia which can result in overdosing and related complications. 5, 6, 7, 8

Opioids-related adverse effects

Each year, worldwide:

  • 50% of surgical patients suffer from moderate to severe post-operative pain9, 10, 11

  • 12% of surgical patients suffer from adverse events due to analgesic medications, leading to12:

    • 3.3 extra days of hospitalization

    • 27% extra cost per patient

    • Increase in re-admissions

  • Post-operative nausea, vomiting (PONV)
  • Respiratory depression
  • Induced opioid hyperalgesia
  • Constipation
  • Delirium
  • Delayed post-operative recovery
  • Reduced patient satisfaction

  • Post-operative pain
  • Hypertension, tachycardia
  • Heart ischemia
  • Increased morbidity
  • Delayed post-operative recovery
  • Reduced patient satisfaction

By using the PMD-200™ in the critical care units, where patients under general anesthesia are unable to communicate their pain, anesthesia teams can monitor the patient’s nociceptive state and the analgesic effect – avoiding excessive use or underuse of analgesics.

What Experts say about NOL® Index

"Getting the right dose of anti-nociceptive medications matters. Too little, and patients wake up in pain. Too much, and patients are at risk of drug-related complications."

Prof. Daniel Sessler, Head of Department of Outcomes Research, Cleveland Clinic, Ohio, USA. A member of Medasense’s advisory board.

To read more about Pain During Surgery and its Objective Measurement


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  2. Acute pain management. Dickerson DM, Anesthesiol Clin. 2014 Jun;32(2):495-504
  3. Preventing Chronic Pain following Acute Pain: Risk Factors, Preventive Strategies, and their Efficacy. Kai McGreevy, Michael M. Bottros, Srinivasa N. Raja,  Eur J Pain Suppl. 2011 Nov 11; 5(2): 365–37
  4. Persistent postsurgical pain: risk factors and prevention, Prof Henrik Kehlet, Prof Troels S Jensen, Prof Clifford J Woolf, Lancet 2006;367:1618-25
  5. Opioid induced nausea and vomiting. Smith HS1, Laufer A2. Eur J Pharmacol. 2014 Jan 5;722:67-78.
  6. Multimodal approach to control postoperative pathophysiology and rehabilitation. Kehlet H. Br J Anaesth 1997; 78: 606–17
  7. Post-op pain services. Gayatri,P (2005).. Indian J. Anaesth. 49 (1) : 17-19
  8. Postoperative Opioid-induced Respiratory Depression: A Closed Claims Analysis. Lorri A. Lee, Robert A. Caplan, Linda S. Stephens, Karen L. Posner, Gregory W. Terman, Terri Voepel-Lewis, Karen B. Domino. Anesthesiology 03 2015, Vol.122, 659-665
  10. Incidence, patients satisfaction, and perceptions pf post-surgical pain: Results from a US national survey. Current Medical Research and Opinion. Gan TJ, Habib AS, Miller TE, White W, Apfelbaum JL. (2014)2014;30(1):149–60
  11. A Prospective Multicenter Study to Improve Postoperative Pain: Identification of Potentialities and Problems. Pogatzki-Zahn E, Kutschar P, Nestler N,Osterbrink J (2015) PLoS ONE 10(11): e0143508
  12. Journal of Pain & Palliative Care, 2013